1. Field of the Invention
In accordance with the classification of art as established in the U.S. Patent Office this invention is found in the general Class entitled, "Agitating" (Class 259) and the subclass therein entitled, "miscellaneous" (subclass 1) which has been further identified in this subclass as "1r" and "Digest 43". The method of making a vibration apparatus as in the embodiment shown is found in the general Class entitled, "Metal Working" (Class 29) and the subclass therein of "impellers" (subclass 156.8).
2. Description of the Prior Art
Air turbines are not new and making the rotor with an eccentric weight is also well known as seen in U.S. Pat. No. 3,074,151 to KROECKEL as issued on Jan. 22nd, 1963. Another patent using the same general concept includes U.S. Pat. No. 2,875,988 to WYSONG as issued on Mar. 3rd, 1959. Other air driven vibrators also generally used include balltype vibrators as seen in U.S. Pat. to PETERSON, No. 2,793,009 as issued on May 21st, 1957 and No. 2,917,290 as issued on Dec. 15th, 1959. In these apparatus as well as others known to the applicant the noise levels at and during normal operation exceed the tolerance levels for continuous duty operation ie. 85 db) as established by the Federal Occupational Safety and Health Act of 1970.
The turbine-type pneumatic vibrator of this invention and the others noted in the cross referenced applications, as reduced to practice and extensively tested and used in commercial installations, operate substantially continuously at noise levels well below the established 85 db and with the associated muffler operate at levels of 60 to 70 db. This, of course, falls well within the safety limits of this federal standard. In sharp contrast to this "quiet" vibrator is the ball-and-race vibrator now and for the past several years in extensive use. This ball-and-race vibrator is shown and described in U.S. Pat. No. 2,793,009 as issued on May 21st, 1957 and No. 2,917,290 as issued on Dec. 15th, 1959 both to PETERSON. The noise level usually found in the installations employing these ball-and-race vibrators is often in excess of 100 db. This noise level for periods of eight or more hours, of course, is unacceptable.
In the present invention the size of the rotor, the number and depth of teeth used therewith and the normal operating range of air pressure used to drive the vibrator are closely related factors. The air turbine of this invention uses a close limit control of these factors to successfully insure that the safe requirements for a "quiet" operation of the vibration apparatus is met or exceeded.
The turbine members in the present invention are formed with the turbine blades in an annular or ring-like pattern and with the blades extending transversely from and normal to the side of the turbine rotor. The housing associated therewith has its inlet and outlet arranged to direct the flow to and from the chamber as a bifurcated or diverted flow.